The background description provided here is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Substrate processing systems are typically used to deposit and etch thin film on substrates such as semiconductor wafers. The substrate processing systems generally include a processing chamber, a plasma generator, a gas delivery system, a gas distribution device and a substrate support. A gas mixture is introduced into the processing chamber and plasma may be used to initiate chemical reactions.
Inductively-coupled plasma may be generated by one or more transformer-coupled plasma (TCP) coils. The TCP coils receive radio frequency (RF) power supplied by an RF power generator. A dielectric window, constructed of a material such as ceramic, is incorporated into an upper surface of the processing chamber. The dielectric window allows the RF power from the TCP coils to be transmitted into the processing chamber. The RF power excites gas molecules within the processing chamber to generate plasma.
An RF bias source supplies RF bias power to the substrate support. The RF bias power can be used to increase a DC bias (a difference in electrical potential between a surface within the processing chamber and ground) and/or a sheath potential (a potential of the plasma) to increase the energy with which charged particles in the plasma strike the substrate. The RF bias power may be adjusted by a process recipe.
Some substrate processing systems implement a rapid alternating process (RAP). The RAP alternates etching and deposition cycles. Different process parameters are used for the etching and deposition cycles. These process parameters may include, but are not limited to, different gas chemistries, pressures, RF bias voltages, inductive coil voltages, etc.